1. Argonne’s Rôle in ZEUS José Repond Argonne National Laboratory DOE Visit, Germantown, March 11 th, 2004

2. Question Necessary ? What happens to ZEUS without ANL participation? Unique ? Could any other institution replace ANL? Impact on other ANL projects ? Does participation in ZEUS help with other ANL projects? Review ANL contributions to ZEUS Overview of current involvement Answer the question…

3. ANL contributions to ZEUS: Hardware Description Uranium – Scintillator sandwich calorimeter 32 Modules each weighing 12 tons Compensating → world’s best hadronic energy resolution Built by collaboration of 10 US institutions Argonne’s rôle Mechanical design + prototyping Cladding of Uranium plates Fabrication of mechanical structures Mechanical assembly + tests Mounting of electronics Tests with cosmic rays (all modules) Installation in experiment Commissioning of calorimeter Operation and maintenance

4. ANL contributions to ZEUS: Hardware Description Receives input from calorimeter regions Calculates various quantities Total calorimeter energy Total transverse energy E T Number of isolated electrons Number of isolated muons …. Sends information to Global FLT Extremely complex system Necessary component for data taking Argonne’s rôle Concept Design Prototypes + tests Fabrication Commissioning Operation and maintenance

5. ANL contributions to ZEUS: Hardware Description Located in front of Barrel EM Calorimeter Consisting of 32 cassettes with 13 tiles each Scintillator with fiber readout into PMTs Argonne’s rôle Proposal Prototyping Design Fabrication Installation Commissioning Operation and maintenance Physics analysis Electron energy corrections Hadron jet energy correction Prompt photon physics analysis

6. ANL contributions to ZEUS: Hardware Description Tracker in rear direction Precision electron angle Scintillator strips with fiber readout Argonne’s rôle Project management First level trigger Design, prototyping and fabrication Commissioning Physics analysis Alignment F 2 (x,Q 2 ) measurements Operation and maintenance

7. ANL contributions to ZEUS: Hardware Description Covers angles between 5 0 – 25 0 11040 tubes Reuse of existing rear-end electronics (2000 channels) Argonne’s rôle Design Prototype Fabricate Test Contribution to recent repair Continuous support Physics analysis Development of Kalman tracking filter Measurement of charm production in forward direction Front-end readout electronics

8. ANL contributions to ZEUS: Physics output Physics chairman Physics group coordinators Exotic searches Structure function measurements Hadronic jets and QCD Members in ZEUS editorial panel Diffraction 1/29 Structure Functions 5/22 Hadronic Jets and QCD 9/54 Heavy Flavors 1/13 Exotic Searches 0/18 16/136 ZEUS physics papers with major Argonne involvement

9. ANL contributions to ZEUS: Physics output Pentaquark search 2004 Electroweak unification 1995 Charm structure function 2004 Diffractive cross sections 2002 Precision jet physics 2001 In collaboration with University of Wisconsin In collaboration with University of Wisconsin

10. ANL contributions to ZEUS: Management Deputy Rik Yoshida 2000 – 2002 Spokesperson Rik Yoshida 2003 – 2006 Calorimeter Barrel Presampler Small Angle Rear Tracker Detector Calorimeter FLT Processor Run

11. ANL contributions to ZEUS: at present Manpower 3.25 staff 2.0 retirees 2.0 students Calorimeter FLT Processor Small Angle Rear Track Detector FLT Straw Tube Tracker Front-end Electronics Barrel Presampler Calorimeter Shift leaders Argonne solely responsible Pentaquark searches Forward jet measurements Charm + jet in photoproduction Beauty production cross sections Prompt photon photoproduction Spokesperson until end of 2006 Coordination of QCD physics group Members in ZEUS editorial board Given manpower limits: very strong contribution ANL initiative Major Argonne rôle

12. Back to the question Necessary? Without ANL contributions, ZEUS drastically weakened Hardware contributions Maintenance of CFLTp and SRTD FLT probably not possible Barrel presampler would be turned of Conceivably the end of ZEUS (and HERA?) Contribution to running of experiment with shift leaders Physics analysis Leadership of QCD group would be significantly weakened Two students left hanging Management Rik would have to step down as spokesperson

13. Back to the question Unique? Excellent mechanical engineering Assembly facilities Excellent electronic engineering Coupled with Long term commitment to experiment (other people work on the LHC) Unique knowledge of crucial components of ZEUS Deep and broad understanding of physics (QCD) Understanding of the underlying physics Long expertise in building calorimeters HRS EM, CDF EM, Soudan II, ZEUS, Minos, ATLAS, LCD Expertise in Monte Carlo simulations EGS for ZEUS, Geant4 for LCD Expertise in photon/electron/jet identification Prompt photon analysis on CDF, ZEUS Jet physics on ZEUS Heavy flavor physics on CDF, ZEUS Deep understanding of QCD, DIS, etc… Unique contributions to ZEUS in the PAST due to Unique contributions to ZEUS NOW due to

14. Back to the question Impact on other ANL projects? CDF, ATLAS Structure Functions Overlapping interest in Jet physics Heavy flavors CTEQ Linear Collider Detector R&D Applying expertise to development of hadron calorimeter Strong ties with European groups through HERA community Theory group Common interest in Quarkonia Heavy flavor production Jet physics

15. Conclusions Exceptionally strong ZEUS and HERA rely on it Strong interaction with other ANL projects Physics involvement necessary for future projects Broadening the US HE physics program